Despite significant advances in therapy, diabetes remains a major cause of morbidity and mortality in the developed world and early detection of diabetes is an area of major public health importance. However, it has been estimated that as many as 50 percent of individuals with diabetes are undiagnosed. It is for this reason that up to 30 percent of patients with “newly diagnosed” type II diabetes already have evidence of systemic complications at the time of diagnosis, data which suggest that the disease has been present already for 5 to 10 years.
Current techniques for screening for diabetes include a fasting glucose in excess of 140 mg/dL or higher on two occasions, or symptoms of uncontrolled diabetes with a random blood glucose in excess of 200 mg/dL, or a positive oral glucose tolerance test. In addition, the use of glycosylated hemoglobin levels has recently been advocated such that individuals with levels above 7.0 percent are considered to have early evidence of disease and thus are potential candidates for diet, exercise, or pharmacologic intervention.
Unfortunately, none of these tests have been found to detect all incident cases of diabetes, and the poor reproducibility and clinical inconvenience of the oral glucose tolerance test has limited its application. Moreover, accumulating data suggests that the beneficial effects of certain preventive and therapeutic treatments for patients at risk for or known to have diabetes differs in magnitude among different patient groups. At this time, however, data describing diagnostic tests to determine whether certain therapies can be expected to be more or less effective in the prevention and treatment of diabetes are lacking.
C-reactive protein is a known marker for underlying systemic inflammation. Elevated levels of C-reactive protein have been described among patients with overt clinical evidence of diabetes and among individuals with evidence of glucose intolerance. However, it has been uncertain whether statistical associations observed in these prior studies of patients with overt disease are causal, are due to short-term inflammatory changes, or are due to interrelations with other risk factors such as obesity and hyperlipidemia.
A need exists for the development of tests that assess the risks for an individual developing future diabetes or diabetic complications.